Huge reservoir of water found under surface on Mars

Imagine discovering an entire ocean hidden beneath the surface of Mars. Scientists have found evidence that an immense reservoir of liquid water may lie deep underground within the Martian crust—enough to fill oceans on the planet’s surface.

A study released on Monday using data from NASA's Mars InSight lander shows evidence of liquid water far below the surface of the fourth planet, advancing the search for life there and showing what might have happened to Mars' ancient oceans.

The data indicates that this hidden water is located about 11.5 to 20 kilometers below the surface, within fractured igneous rocks—rocks that were formed from cooling and solidifying magma or lava.

According to Vashan Wright, a planetary scientist from the University of California, San Diego, "At these depths, the crust is warm enough for water to exist as a liquid. At more shallow depths, the water would be frozen as ice." This suggests that Mars could have conditions favorable for microbial life, either now or in the planet's past.

The discovery is based on how seismic waves travel through Mars' crust. The InSight lander, which operated from 2018 until 2022, was able to measure the speed of these waves as they moved through different layers of the planet.

The speed of the waves varies depending on the type of rock, whether the rock has cracks, and what fills those cracks—such as liquid water. By combining these seismic measurements with gravity data and rock physics models, Wright and his team concluded that the presence of liquid water within these fractured rocks is the best explanation.

"A mid-crust whose rocks are cracked and filled with liquid water best explains both seismic and gravity data," Wright noted. If the findings from the InSight location are representative of the planet as a whole, it’s estimated that the water could fill a global ocean up to 1-2 kilometers deep.

This potential reservoir offers a new and exciting place to search for life on Mars. As planetary scientist Michael Manga from the University of California, Berkeley, pointed out, "On Earth, we find microbial life deep underground where rocks are saturated with water and there is an energy source." If similar conditions exist on Mars, they might support life as well.

Insight also detected Marsquakes up to about a magnitude of 5, meteor impacts and rumblings from volcanic areas, all of which produced seismic waves that allowed geophysicists to probe the interior.

While accessing this underground reservoir is beyond our current capabilities, the discovery helps answer questions about Mars' geological history and highlights another promising area for future exploration.

With additional input from Reuters.